During the transition of power in the US, it’s a tradition for outgoing presidents to leave a note to their successors.
Mr Trump broke a series of traditions during the transfer of power to Mr Biden’s administration, including insisting the result of the November election was fraudulent, and never acknowledging his successor’s win.
But Mr Biden revealed on Wednesday, Mr Trump had left him a “generous” letter.
“The president wrote a very generous letter,” Mr Biden said. “Because it was private, I won’t talk about it until I talk to him. But it was generous.”
Speculation on social media was sent into overdrive, with some users posting what they imagined a letter from Mr Trump to Mr Biden might look like.
The results were predictably hilarious.
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A number of Twitter users imagined Mr Trump lamenting his loss, while others joked he’d be asking Mr Biden for a pardon.
Others joked he’d give Mr Biden advice about the White House bathroom.